1. Field of the Invention
The present invention relates to a pattern forming apparatus which applies an application liquid containing a pattern forming material upon a substrate surface and forms a pattern.
2. Description of the Related Art
Among techniques for forming a predetermined pattern on a substrate surface is a technique which requires applying onto a substrate surface an application liquid containing a pattern-forming material and curing the application liquid, and various techniques to realize this have been proposed. For instance, JP2007-222770A discloses a structure of a nozzle which can be applied to the pattern forming technique mentioned above. According to the technique described in this patent publication, the tip of the nozzle is formed by laying one atop the other a plurality of parts which have dents, grooves and the like which serve as a feeding path for the application liquid so that it is possible to disassemble the nozzle. The parts are firmly held from outside in an attempt to prevent leakage from gaps between the parts.
However, an even higher aspect ratio of patterns and an even faster speed of forming the patterns than before are demanded these days. That is, the requirement is to form a pattern having a high ratio of the height of the pattern to the width of the pattern (aspect ratio) in an even shorter period of time than before. To realize this, it is necessary to develop a technique which achieves extrusion of a highly viscous application liquid with an even greater pressure (such as 1 MPa or greater) than in the past. The conventional nozzle structure described above sometimes fails to fully meet this requirement. In more specific terms, a pressure loss is created as the high inner pressure slightly bends and distorts the nozzle parts or as the liquid leaks out from the gaps between the parts due to the capillary effect. This from time to time makes it impossible to perform appropriate discharge control which is for controlling the cross-sectional shape, the amount or the like of the application liquid which is discharged at a discharge outlet.